Radiosurgery has become increasing popular in recent years. The aim of radiosurgery is for a large dose of radiation to be targeted to an affected area, while the damage to surrounding normal tissue is kept to a minimum. This is can be very useful in treatment areas where the surrounding tissue performs a critical function, for example the brain and lungs.
Radiosurgery was originally developed to treat brain tumors, but has since been expanded to treat many other target organs, including: breast, lung, prostate, liver, spine, kidney, adrenal, pancreatic, bone, abdominal and soft-tissues. As the utility of radiosurgical methods increase, the need to address the concerns with the procedure become even more pressing as more patients will be undergoing the treatment.
To treat a single tumor with radiosurgery dozens or hundreds of radiation beams are targeted to enter the body from different angles. Each beam intersects the tumor and the region where all the beams intersect results in a summation of the radiation of each individual beam and the tumor receives the full dose. However, the beams must each pass through normal tissue to reach the intended target and therefore those normal tissues also receive a partial radiation dose. Since it is such a small dose that passes through with any single beam, the radiation does not result in much damage to the normal tissues and is usually tolerable to the patient.
Brain metastases are a common clinical problem in cancer patients. They occur in 20-40% of all cancer diagnoses, especially in lung, breast, kidney and melanoma cancer patients. As these numbers continue to increase, there will be more and more patients undergoing radiosurgery for the treatment of their tumors.